Not being a 'fly on the wall' when it happened, I can only hazzard a guess.
You have bad engine mounts.
You have bad center drive line support.
You have periodic wheel sympathetic unbalance.
You stopped with the tyre bulge at the bottom.
Transmission was hunting between gears after power loss.
Bad road maintinence by local authority.
You passed through a time warp .
10 dollars worth of gas in a 500 will make the tank floor damp and that's about it ! That equates to just over 3 gallons...the fuel lines hold that much !
Those beasts get 5 to 8 mpg during the warm up cycle. If you accelerate onto the interstate at the same time, think 4 mpg.
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